Detecting Metastases

When they spread outward, away from the prostate, prostate cancer cells tend to settle first locally, affecting the pelvic bone, the lower spine, and the upper thighs. Many men experience pelvic area pain as a first sign that the cancer might have spread to the bone, and aggressive management strategies are used to manage the pain, minimize the effects of the metastases, and avoid complications caused by the metastases.

For men with suspected bone metastases, or for men with advanced disease who are considered at risk for developing bone metastases, detection tools will be used to pinpoint the location of the metastases in order to better assess how to treat it.

The "gold standard" test for bone metastases is the bone scan. A radioactive substance that acts like a dye is injected in a vein, and images of the entire skeleton are taken. The dye-like material highlights areas where bone tissue is changing rapidly—a hallmark effect of prostate cancer bone metastases.

Bone scans can detect even small amounts of increased bone metabolism, but not all changes are caused by prostate cancer bone metastases. The dye might be detecting changes in the bone due to a previous fracture, infection, arthritis, or even bone loss that can result from the use of hormone therapy. A complete medical history can help doctors better assess the results of the bone scan and therefore determine the best treatment approach.

Other types of scans, such as x-rays, CT scans, MRIs, and PET scans, are typically used to monitor the effects of the metastases over time and to determine whether any new changes on a bone scan are caused by bone metastases.

Additional Reading:

Chapter 8: Managing Bone Metastases and Pain